I started with a KS Supernatural.
No issues for 3 yrs, 3 months until I ended up cracking the saddle-rail mounts. Since that model had no replacement parts, non-rebuildable I binned it & replaced it w/a KS Lev & added a Southpaw lever...the drooper pole has been the best investment I ever made for MTB-ing!!
For my rigid snow bike, I wanted to try one, but didn't want to shell out much so went with a TMars post, $90.
That made it through 2 winters w/almost no maintenance before it decided to quit. The pin that holds the shaft in position was the issue.
If you want to give a drooper pole a shot on a budget, I'd suggest the Tmars ($66 now - I may grab another).